The invention is based on a measuring instrument. DE 29 23 644 C2 has disclosed a sensor for travel measurement which has a cylindrically embodied frame made of a ferromagnetic material. A permanent magnet is moved in a sliding fashion in the frame and its movement is transmitted with the aid of a tappet and is proportional to the movement of a component. Furthermore, a magnetic field sensitive element is disposed in a gap in the frame and is consequently enclosed in the magnetic circuit produced by the magnet and its output signal is proportional to the movement of the magnet. But the sensor is relatively complex and expensive. Furthermore, a high friction losses can be produced with the movement of the magnet, which can distort the output signal.
The measuring instrument according to the invention, has the advantage over the prior art that for a low assembly cost, a linear output signal can be determined for travel measurements. The distance to be determined is relatively long and can, for example, be 10 mm. In addition, because of its simple construction, the sensor can be incorporated without excessive alteration and assembly costs into systems such as an exhaust gas recirculation valve, valve stroke detection, body spring deflection, or transmission control.